---

name: dig description: systematic investigation and debugging methodology. hypothesis-driven analysis with verification agents. use for incident response, codebase archaeology, dependency mapping, root cause analysis, or any investigation requiring verified findings.

dig

structured approach to investigations that produces verified, actionable findings.

load first: review — provides epistemic standards (trace or delete, label confidence, falsify don't confirm). dig assumes these are active.

core principles

1. trust code over assumptions — never assume intent. check git history.
2. scripts > docs — extraction scales, documentation doesn't.
3. bidirectional analysis — traverse dependencies forward AND reverse.
4. autonomous discovery — use seeds and graph traversal, don't hardcode.

investigation phases

phase 1: map

scope the problem. identify seeds (entry points) for traversal.

Copy1. define the question precisely
2. identify seed artifacts (files, functions, types, API endpoints)
3. choose traversal strategy:
   - reverse: seed → importers → consumers (finds affected scope)
   - forward: seed → dependencies → leaves (finds implementation details)
   - bidirectional: both (complete picture)
4. extract, don't document — write scripts that produce structured output

when to check git:

• git blame <file> — who wrote this line? when? why?
• git log -p --follow -- <file> — full history of a file
• git log --all --oneline -- <path> — find when something was introduced
• git log --grep="<term>" — find commits mentioning a concept

phase 2: verify

spawn verification agents to fact-check analysis claims.

Copyfor each major claim:
  1. spawn a verification agent with ONLY the claim + file paths
  2. agent must independently confirm or refute
  3. record: VERIFIED, REFUTED, or INCONCLUSIVE

verification agent prompt template:

Copyverify this claim: "<claim>"
files to check: <file list>
do not assume the claim is correct.
check the actual code and report what you find.

anti-patterns:

• trusting oracle/LLM statements without code verification
• assuming wrapper names without grep confirmation
• documenting before extracting

phase 3: synthesize

structure findings for consumption.

tables for enumeration:

trees for relationships:

CopyRootComponent
├── ChildA → uses Feature
└── ChildB
    └── GrandchildC → also uses Feature

appendices for exhaustive lists (don't clutter main findings).

output structure

Copy# <investigation title>

## summary
one paragraph. what did we find?

## context
why are we investigating? link to trigger (slack, ticket, etc.)

## findings
### 1. <finding title>
<evidence with file links>
<code snippets>

### 2. <finding title>
...

## open questions
numbered list of things we couldn't verify

## appendices
- [detailed-list-a.md](./detailed-list-a.md)
- [detailed-list-b.md](./detailed-list-b.md)

## related threads
table of amp thread links with descriptions

verification agent pattern

when coordinating investigation:

Copy1. spawn analysis agents (stores, routes, components, etc.)
   - each produces claims with file:line citations
   
2. collect claims from all analysis agents

3. spawn verification agents (1 per analysis agent)
   - input: claims + file paths only
   - output: VERIFIED/REFUTED/INCONCLUSIVE for each claim
   
4. synthesizer combines verified claims into report

this catches:

• oracle hallucinations
• outdated information
• claims about files that changed since analysis started

autonomous discovery

never hardcode component lists. instead:

Copy# start from seeds
SEEDS=$(grep -rl "import.*from.*deprecated-lib" --include="*.ts")

# build import graph
for seed in $SEEDS; do
  # find importers (reverse)
  grep -rl "import.*from.*$seed" --include="*.ts"
  
  # find imports (forward)  
  grep "^import" "$seed" | extract_paths
done

bidirectional traversal discovers components you didn't know existed.

when to use

• production incident with unclear root cause
• "how does this feature actually work?"
• dependency upgrade impact assessment
• "why was this designed this way?" (git archaeology)
• mapping blast radius of a refactor

references

• AXM-10608-investigation-report.md — multi-dataset assumption mapping
• 2025-10-22T21:50-process-summary.md — rc-menu dependency discovery evolution